Why a doctor who uses the device should write this
I bought this device, I use it, and I have spoken about it to other doctors. Every one of those is a reason to be suspected of enthusiasm, and every one of them is a reason to write the evidence down plainly. A device that is good for the right patient does not need the evidence inflated, and a patient deserves to know how much of what they are told is study and how much is judgement.
So this is an evidence review: what has been published, where, by whom, and what it can bear. It is not a review of patients or results, and it does not contain any. Where I give an opinion I mark it as one.
What XERF is, in the class it belongs to
XERF is a monopolar radiofrequency device. Monopolar radiofrequency passes an electrical field through the skin to a return plate; tissue resistance turns the field into heat in the dermis and the layer beneath, and cooling at the surface keeps the heat below it. The body's response to that controlled heat is a slow remodelling of collagen and elastin over weeks to months. That is the same mechanism as every monopolar radiofrequency device since the class appeared in the early 2000s.
What distinguishes newer devices in the class is control: more than one frequency, real-time reading of tissue impedance so that energy delivery adjusts pulse by pulse, and integrated cooling. XERF uses two frequencies, 6.78 and 2 MHz. Those are engineering choices about how the heat is distributed. They do not change the biology, and they should not be read as a claim that the device does something the class cannot.
The evidence for XERF itself, as of August 2026
I searched PubMed for the device name and for its dual-frequency description on 17 August 2026. There is no clinical trial indexed under the name XERF. Two publications are relevant.
The first is a 2025 paper in Lasers in Medical Science: a computational model of how 6.78 and 2 MHz monopolar radiofrequency distribute heat in layered skin, plus in-vivo work in porcine skin. In that model the 2 MHz field heated more broadly and deeply into fat, the 6.78 MHz field heated more locally along the fibrous septa, and the two together concentrated heat at the junction of dermis and fat. Histology in the pigs showed collagen and elastin remodelling in the dermis and septa, more extensive with the dual frequency, and no fat-cell death. Several of its authors are employed by the manufacturer. It is a mechanistic study in an animal, and it says nothing directly about how a face looks at six months.
The second is a short 2024 report in Skin Research and Technology titled as histological evidence for dual-frequency non-invasive monopolar radiofrequency in skin tightening, written by the manufacturer's clinical development team, with an erratum published in 2026. I mention it because it exists and because you may be shown it; I would not build expectations on a manufacturer's histology note.
That is the device-specific file. It is thin, and I say so in the consulting room. Everything else the device leans on is evidence about the class.
The evidence for the class
The oldest layer is histology. A 2004 pilot study in Archives of Dermatology looked at skin treated with an early monopolar device and reported thickened collagen fibrils and increased type I collagen messenger RNA, the biological signature of remodelling. It established that the mechanism is real. It did not, and could not, say how much a face improves.
The broadest layer is a 2022 systematic review in Lasers in Surgery and Medicine that identified 121 articles on radiofrequency for the face and neck. It found improved laxity, elasticity and global appearance, histology consistent with new collagen and elastin, and, on safety, one serious adverse event (a neck fistula) across the whole body of work. Its own caveat is the important one: most of the positive findings are subjective improvement ratings, and patient satisfaction was highest among those who wanted modest change. Read that sentence twice; it is the honest summary of the class.
The most useful layer for a patient choosing between tools is the pair of small head-to-head trials against micro-focused ultrasound. A 2017 randomised evaluator-blinded trial treated 20 necks with either monopolar radiofrequency or micro-focused ultrasound and found both improved neck laxity through six months, with no statistically significant difference between them, and more procedural pain with the ultrasound. A 2019 split-face randomised trial treated 20 faces with ultrasound on one side and radiofrequency on the other and again found improvement on both sides and no statistically significant difference in laxity, satisfaction or adverse events. Two trials of 20 patients cannot show two treatments are equal. They can only fail to show a difference over six months, which is a weaker and more honest statement.
The safety layer, for the skin types most of my patients have, is a 2023 review in Dermatologic Surgery of 35 studies of radiofrequency and radiofrequency microneedling in skin of colour: seven studies noted transient post-inflammatory hyperpigmentation, one noted mild prolonged hyperpigmentation, one reported permanent scarring, and the authors judged the overall risk low while noting that most of the studies were not of strong quality. Older monopolar devices used at aggressive settings in the mid-2000s also drew reports of contour change from fat loss under the skin, which is the reason modern devices read tissue as they go and cool the surface, and the reason settings matter more than brochures.
What that evidence can carry, and what it cannot
It can carry this: for early to moderate laxity of the face, jawline and neck, monopolar radiofrequency produces a modest, gradual tightening in most treated patients, is comfortable for most, and is comparable in the small trials that exist with the better-studied ultrasound alternative. That is enough to offer it, with modest expectations, to the right patient.
It cannot carry a promise of a particular result, a durability figure, or any claim that XERF outperforms other devices in its class or another class. There is no study that says any of those things. When you see them said, you are reading a brochure.
It also cannot carry the device onto the wrong face. No amount of radiofrequency restores lost volume, and no radiofrequency device lifts a face whose support has descended past what remodelling can reach. Those are the two commonest reasons a tightening treatment disappoints, and they are decided at the assessment, not by the machine. Who XERF is for, and who it isn't sets that out.
What I tell patients, and what I would need to see
In the room I say roughly this: the class works, modestly and gradually; the device is a well-controlled member of the class; the evidence specific to it is preclinical so far; two sessions, a result that builds over months, maintenance when your skin asks for it; and if your laxity is deeper than this tool reaches, I will say so and we will talk about something else. My own experience of the device, on my own face and in clinic, is one data point and I present it as one; it is written up separately.
What would move me from offering it with modest expectations to recommending it with confidence: an independent, registered clinical trial with blinded photographic assessment, at least twelve months of follow-up, and a comparison arm. Until then, the honest position is the one above, and this page will be updated when the literature changes. The date at the top is the date it was last checked.
Sources
Checked on PubMed on 17 August 2026. Where a study's authors are employed by a device manufacturer, that is noted.
- Ko K, Ryu HG, Park J, et al. Computational modeling and histologic analysis of 6.78- and 2-MHz monopolar radiofrequency-induced thermal reactions. Lasers in Medical Science 2025; 40(1): 501. Computational model plus porcine skin; several authors employed by the manufacturer. PubMed 41315066
- Hong J, Ryu HG, Park C, et al. Efficacy of dual-frequency noninvasive monopolar radiofrequency in skin tightening: histological evidence. Skin Research and Technology 2024; 30(6): e13821. Authored by the manufacturer's clinical development team; erratum 2026. PubMed 38881041
- Zelickson BD, Kist D, Bernstein E, et al. Histological and ultrastructural evaluation of the effects of a radiofrequency-based nonablative dermal remodeling device: a pilot study. Archives of Dermatology 2004; 140(2): 204 to 209. PubMed 14967794
- Austin GK, Struble SL, Quatela VC. Evaluating the effectiveness and safety of radiofrequency for face and neck rejuvenation: a systematic review. Lasers in Surgery and Medicine 2022; 54(1): 27 to 45. 121 articles. PubMed 34923652
- Jones IT, Guiha I, Goldman MP, Wu DC. A randomized evaluator-blinded trial comparing subsurface monopolar radiofrequency with microfocused ultrasound for lifting and tightening of the neck. Dermatologic Surgery 2017; 43(12): 1441 to 1447. n = 20. PubMed 28902019
- Alhaddad M, Wu DC, Bolton J, et al. A randomized, split-face, evaluator-blind clinical trial comparing monopolar radiofrequency versus microfocused ultrasound with visualization for lifting and tightening of the face and upper neck. Dermatologic Surgery 2019; 45(1): 131 to 139. n = 20. PubMed 30531187
- Alam M, White LE, Martin N, et al. Ultrasound tightening of facial and neck skin: a rater-blinded prospective cohort study. Journal of the American Academy of Dermatology 2010; 62(2): 262 to 269. n = 35. PubMed 20115948
- Oni G, Hoxworth R, Teotia S, et al. Evaluation of a microfocused ultrasound system for improving skin laxity and tightening in the lower face. Aesthetic Surgery Journal 2014; 34(7): 1099 to 1110. 93 evaluated. PubMed 24990884
- Haykal D, Sattler S, Verner I, et al. A systematic review of high-intensity focused ultrasound in skin tightening and body contouring. Aesthetic Surgery Journal 2025; 45(7): 690 to 698. 45 studies, pooled devices. PubMed 40184185
- Humphrey VS, et al. Microfocused ultrasound with visualization: a systematic review of adverse events and risk of subsequent facelift compromise. Dermatologic Surgery 2025; 51(4): 424 to 429. PubMed 39625163
- Syder NC, et al. Radiofrequency and radiofrequency microneedling in skin of color: a review of usage, safety, and efficacy. Dermatologic Surgery 2023; 49(5): 489 to 493. 35 studies. PubMed 36826381
- Niaz G, et al. Fractional radiofrequency microneedling as a monotherapy in acne scar management: a systematic review of current evidence. Clinical, Cosmetic and Investigational Dermatology 2025; 18: 19 to 29. 16 studies, 481 patients. PubMed 39781098
This is a review of published evidence for general information. It is not a recommendation for treatment, and it does not replace an assessment.
